The height of a tree is 10
10
meters long and it grows 1
1
cm in a year.
Then its height after one year = 10
10
meters 1
1
cm
Its height after 3
3
years = 10
10
meters 3
3
cm
Its height after 6
6
years = 10
10
meters 6
6
cm
Its height after x
x
years = 10
10
meters x
x
cm
Where x
x
represents an unknown number. From the last line, we can find height of the tree after a certain number of years by taking x
x
equal to that number. For example, we simply let x=15
x
=
15
, 25
25
and 55
55
. Thus, the value of x
x
depends on our choice. We can give x
x
any value or number we want. In other words, the value of x
x
is not fixed, it varies from one situation to the other. Therefore, we call x
x
a variable whereas 10
10
is a fixed number whole value does not change. So 10
10
therefore is called a constant.
Read more: http://www.emathzone.com/tutorials/basic-algebra/algebraic-expression.html#ixzz4fDkFcbpZ
Answer: D ( 17/20)
Step-by-step explanation:
The two choices are:
The ‘standard’ tariff charges = $0.10 per unit
The ‘day/night tariff’ = $0.12 per unit for each unit consumed between 06:00 and 22:00 but only $0.05 for each unit consumed between 22:00 and 06:00
The day time is between 22:00 and 06:00
Time = 22 - 6 = 16 hours
Let assume that the charges are unit per hour.
For standard tariff = (16 × 0.10) + 0.2
Standard tariff = 1.6 + 0.2 = 1.8
For day/night = (16 × 0.12) + 0.2
= 1.92 + 0.2
= 2.12
The proportion will be
1.8/2.12 = 17/20 ( approximately)
The answer is y=-8 I’m pretty sure
Answer:
1. 35 - 176 = -141
2. 0.55 × 1.79 = 0.9845
3. 11.38 × 5.46 = 62.1348
Hope it helps and have a great day! =D
~sunshine~